Investigate if `amazon` flavor can be removed

The amazon flavor exists because amazon app store doesn't allow asking the camera permission: https://github.com/ankidroid/Anki-Android/blob/60a823d9c2f7364958b5eaa5a5faee13159b172d/AnkiDroid/src/amazon/AndroidManifest.xml

Since the permission was removed at #14162, investigation is necessary to determine if the flavor can be removed as well, which the main benefit would be decreased release times

Note that the amazon release is currently unavailable because of #14161